Automatic cycle contour finishing machine

ABSTRACT

A longitudinally reciprocable and transversely indexable base carries parallel upright pivots, one mounting a template holder and the other a workpiece holder. The holders each have head and tail stocks to mount a template and a workpiece, respectively, shown as bladelike in nature, for pivotal movement in substantially coaxial alignment. A rotary finishing head engages the workpiece from above and a tracer engages the template from above as the latter is sustained from beneath by a reaction ball camming device. The base is reciprocated by hydraulic cylinder means, and is hydraulically indexed transversely after reciprocatory cycles. The tracer follows the contour of the template, and universal joint and connecting rod linkage means, plus the ball device, operatively articulate the template with the workpiece in such manner that the latter is gradually swung about horizontal and jogged about vertical axes as it travels horizontally beneath the finishing head to finish a compoundly curved turbine or like blade surface. The template tracer maintains the surface of the finishing head in flush, line contact with the workpiece by coaction with limit switch and hydraulic control means.

United States Patent [72] Inventor George R. Carlson 830 Cranbook, Birmingham, Mich. 48009 [21] Appl. No. 779,860

[22] Filed Nov. 29, 1968 [45] Patented June29,1971

[54] AUTOMATIC CYCLE CONTOUR FINISHING Primary Examiner-Othell M. Simpson AnorneyWhittem0re, Hulbert and. Belknap ABSTRACT: A longitudinally reciprocable and transversely indexable base carries parallel upright pivots, one mounting a template holder and the other a workpiece holder. The holders each have head and tail stocks to mount a template and a workpiece, respectively, shown as bladelike in nature, for pivotal movement in substantially coaxial alignment. A rotary finishing head engages the workpiece from above and a tracer engages the template from above .as the latter is sustained from beneath by a reaction ball camming device. The base is reciprocated by hydraulic cylinder means, and is hydraulically indexed transversely after reciprocatory cycles. The tracer follows the contour of the template, and universal joint and connecting rod linkage means, plus the ball device, operatively articulate the template with the workpiece in such manner that the latter is gradually swung about horizontal and jogged about vertical axes as it travels horizontally beneath the finishing head to finish a compoundly curved turbine or like blade surface. The template tracer maintains the surface of the finishing head in flush, line contact with the workpiece by coaction with limit switch and hydraulic control means.

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A. SOLG TILT U ATTORNEYS AUTOMATIC CYCLE CONTOUR FINISHING MACHINE BACKGROUND OF THE INVENTION The finishing machine of the invention is of a belt type employed in the surface finishing and polishing of usually elongated objects having a compound surface curvature in at least two, and ordinarily three, dimensions, such as the turbine compressor blades of an aircraft jet engine, steam turbine blades, plowshares and the like. This is a highly specialized field, in most cases requiring high precision performance, yet inviting high speed and output capacity to the end that the extremely high cost of production, as using present methods and equipment, may be substantially reduced.

More specifically, the machine is of the type in which a special individual template is provided to present the complex, usually multiple-compounded curvature of the blade or other object to be finished, or a substantial surface portion thereof. The template is drivingly coupled to the workpiece, with a feeler unit and a camming reaction unit traversing surfaces of the template, and through these units and coacting limit switch and fluid pressure devices motion is accurately transmitted to a finishing unit as the latter takes engagement with the surface of the workpiece. I am not aware of any prior art patents relating to a correspondingly specialized piece of apparatus.

SUMMARY OF THE INVENTION The equipment is used in the final finishing and polishing of a special surface, such as that of a compressor turbine blade for a fan jet engine, to name an instance in which the full versatility of the equipment comes into play. That is, such an ob ject presents leading and trailing edge portions, which the Ion gitudinal and horizontal movement of the blade holder should parallel as the finishing belt initially comes in contact with and finally departs from after a cycle of strokes beneath the belt during which the blade is mildly oscillated on a horizontal axis. This is particularly necessary in the case of a blade having nonparallel surfaces, and calls for a gradual jogged oscillation of the template and connected workpiece about parallel vertical axes as the blade continues under attack by the belt.

Further in this connection, the polishing belt surface should engage the workpiece, as the blade traverses reciprocably successive polishing cycles, in such manner that the axis of the contact roller backing the belt parallels the direction of workpiece travel, i.e., to effect a true linear engagement of the belt surface with the blade.

The gradual oscillation of the blade workpiece about a longitudinal horizontal axis is effected under the mechanical camlike control of the template by its sustaining ball device. The jogging manipulation of the horizontal angularity of the workpiece and template is controlled by one of two hydraulic cylinder units. However, due to the combined curvature of the surface of the instanced blade surface, the template must transmit and the polishing head must receive a still further compounded oscillatory action, this time about parallel horizontal and transverse axes as a polishing pass takes place, in order that the finishing belt may go about a contact axis paralleling the work surface. This action is under the control of a second hydraulic unit and second connecting rod means, both governed primarily by the template tracer unit and linkage.

As for the horizontal traverse and indexing movements of the template and workpiece holders, these are under the control of a hydraulic cylinder assembly upon the base of which the two holders have a common support. In this arrangement, a platen carrying the holders for horizontal side-to-side action is mounted by very efficient antifriction ball bushings and load rollers upon a second hydraulically powered unit which takes care of the transverse front-to-rear (and vice versa) indexing of the template and workpiece holders beneath the polishing belt as horizontal and longitudinal polishing cycles continue. The last named hydraulic unit is itself mounted by ball bushings and load rollers upon a fixed base support of the machine.

In order to accommodate the compound motion of the template and workpiece holders about horizontal and vertical axes, as described above, they are drivingly coupled together by a slide-type universaljoint of an improved nature, including a telescoping splined shaft and sleeve device permitting relative axial shift of the coupled mechanisms attending a universal drive action transmitted through clevis elements of the joint or coupling.

The equipment also incorporates appropriate motor driven pump means supplying needed pressure to the various hydraulic units mentioned above, under the control of appropriate balance and valving means not germane to the invention but, of course, necessary to the operation of the machine. By the same token the latter incorporates necessary electrical limit switch controls to initiate and terminate the numerous mechanically, hydraulically and pneumatically powered ac tions ofthe equipment.

Although the machine is designated as being polishing or finishing equipment, it is a fact that the rough workpiece to be finished, typically a turbine blade received in a fairly crude surface condition as the product of a ball mill, actually has a considerable thickness of metal removed therefrom in the course of operation of the machine. Therefore, it is to be understood that the principles and structure of the improvement are not limited in application to superficial finishing polishers alone, but have utility in the sense of being highly specialized machine tools.

The automatically cycled contour finishing equipment of the invention is very versatile in regard to the types of workpiece it can handle to shape-compounded curvilinear and rectilinear surfaces. Moreover the automaticity of its control actions may be furthered by installing known numerical control data or tape equipment in combination therewith. It may utilize a belt-type finishing head, as herein illustrated, or an abrasive wheel.

In terms of practical advantages and by comparison with ex isting procedures for a similar purpose, it has been found that time and cost of finishing a typical blade is reduced considerably.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view illustrating in a general way the major workpiece holding, template holding, surface finishing, template feeler and motion imparting and controlling components of the improved machine, but omitting various elec trical wiring and fluid pressure supply provisions associated with these components;

FIG. 2 is a front elevational view of the equipment; FIG. 3 is a side elevational view from the left of FIGS. I and FIG. 4 is a corresponding side elevational view from the right of these figures;

FIG. 4A is a broken top plan view of a part of the structure of FIG. 4;

FIG. 4B is a fragmentary view in enlarged scale of a portion of FIG. 4 at which the finishing belt head is operatively connected;

FIG. 5 is a top plan view, as from line 5-5 of FIGS. 2, 3 and 4, showing hydraulically powered provisions by which the workpiece and template holding sub-assemblies, as supported as a unit by a suitable plate, are traversed horizontally and longitudinally back and forth and indexed transversely in the work finishing cycles;

FIG. 6 is an end elevational view of the traversing and indexing structure, as from the right of FIG. 5;

FIG. 7 is a fragmentary front elevational view, partially broken away and in vertical section, illustrating the head and tail stock type holders for the workpiece and the template, and a universal joint device operatively connecting the holders;

FIG. 8 is a top plan view, partially broken away, of the holder structure of FIG. 7;

FIG. 9 is a side elevational view generally showing the template feeler or tracer unit of the machine and its mount to a fixed upright plate of the latter; a coacting support and reaction ball unit being indicated in dotted line in relation to the template;

FIG. 10 is a front elevation of the subassembly of FIG. 9, indicating in dotted line (and exaggerated degree) the pivotal action of the mount as the unit traces the template;

FIG. 11 is a fragmentary enlarged scale view of the tracer head of the unit or subassembly of FIGS. 9 and 10, as it coacts with the antifriction reaction ball unit, being partially broken away and sectioned vertically on a line corresponding to line -11 of FIG. 10;

FIG. 12 is a fragmentary view in vertical section on line 12-12 ofFIG. 11;

FIG. 13 is a very schematic view indicating the control of the action of the various moving components of the equipment by certain limit switches, and

FIG. 14 is a wiring diagram showing various electrical control components, particularly limit switches which alone are specifically identified hereinafter;

DESCRIPTION OF A PREFERRED EMBODIMENT The machine of the invention is made up of a number of basic component assemblies and subassemblies which it will be attempted to describe in sequence. Referring to FIG. I, the operating parts of the apparatus are mounted upon a very rugged base 10 including a welded angle iron and channel platform structure sustaining a flat horizontal front-to-rear way plate 11. This elongated support way, as shown in FIGS. l6 supports a combined horizontal front-to-rear indexing and horizontal side-to-side hydraulic assembly, generally designated by the reference numeral 12. The assembly 12 breaks down into an upper, side-to-side traversing subassembly or unit 13, which unit moves the template and workpiece reciprocally in continuous strokes at slow speed in the direction of the double-headed arrow A. Unit 13 is supported by a front-to-rear indexing subassembly or unit 14 of hydraulic power assembly 12, which periodically shifts the subassembly 13 in one transverse direction or reversely thereof, as indicated by the double-headed arrow B.

The side-to-side traversing subassembly 13 supports (by means to be described) an elongated rectangular top plate or slide 15 carrying a pair of upright antifriction pivot units I6, 17; and a holding structure 18 for an accurately shaped template T, and a holding structure 19 for a blade workpiece W are respectively mounted in longitudinally spaced relation to one another on the pivots I6 and I7. Holder structures I8, 19 are end-to-end coupled operatively through the agency of a universal joint or coupling 20. A gradual cammed oscillation derived from template T, as the latter is subjected to a fixed ball reaction follower 21, is transmitted from holder 18 through coupling 20 to holder 19 and workpiece W. The resultant motions of the parts are indicated by the letter C in FIG. 1, being about the axis of coupling 20.

The template and workpiece holding structures l8, 19 are operated about the vertical axes of the respective pivot units 16 and 17, as indicated in FIG. 1 by arrows D, through the agency of a hydraulically powered jogger cylinder 22 and a rocker arm and connecting rod linkage, generally designated 23. This takes place, under the control of appropriate hydraulic circulatory and limit switch means, at the end of a reciprocatory side-to-side traverse cycle, or limited number of cycles, of the holders 18 and 19; and the purpose in jogging template T and workpiece W at these intervals is solely to maintain the action of the finishing head H, as constituted by an endless abrasive belt 3! and contact wheel Wh, parallel with the leading and trailing edges of the workpiece W as the belt Br initially takes engagement with and ultimately disengages from the workpiece, as well as parallel with the zones of traverse intermediate these extremes. If the workpiece is parallel-sided, the jogging cylinder 22 and rocker arm linkage 23 may be neutralized or dispensed with.

Such controlled and intermittently continuing jogging adjustment of belt Bt and contact wheel Wh is about an axis at to a vertical plane including the axis of the wheel, and is under the control of a pivoted tracer head 24 located to downwardly engage template T directly above the reaction ball unit 21. Head 24 controls suitable limit switches governing the adjustment of contact wheel Wh in a vertical plane and on the 90 horizontal axis referred to above. The limit switches control a hydraulic tracer and belt head oscillating cylinder and linkage subassembly 25 (FIG. 4A), which is located to the rear of an upright wall 26 of the machine; and pneumatically responsive lift cylinder and dashpot speed control means are provided to make and maintain contact of the tracer head 24 with template T and to govern the speed of the heads action in raising and lowering relative to the template T.

Thus, the tracer head 24, as engaged with the template T from above, has a slight rocking motion imparted to an actual feeler component thereof about a transverse pivotal axis on the feeler head proper. This motion is received as the template T travels horizontally beneath head 24 and is in a vertical plane including the direction of the sidewise traverse. A very limited rocking of feeler component in this manner makes and breaks certain limit switch means, which in turn govern, through solenoid valve and like means, the hydraulic cylinder and linkage subassembly 25.

Subassembly or unit 25, as triggered in response to the limit switch means of tracer head 24, causes dovetail-type adjustable oscillating plate mounts 27, 28 for the tracer and belt finishing heads 24 and H, respectively, to rock slightly about parallel and transverse horizontal axes, with the result that the belt B! of the finishing head maintains flush line working engagement with the surface of the workpiece W.

With the above general objective scheme of operation in mind in regard to the multiple and compounded motion characteristics of the apparatus, and prior to a somewhat more detailed but still not exhaustive description of the basic units or subassemblies mentioned above, it is in order to mention briefly the service equipment associated with the machine for the powering of hydraulic components thereof, the pneumatic positioning of parts, the limit switch control of certain motions, and the like.

Thus, reference being made to FIGS. 1, 2, 3 and 4, an appropriately rated electric motor 30 (FIG. 3) is drivingly connected through coupling means 31 with a hydraulic pump 32 supplied with hydraulic liquid by an accumulator tank 33, the filling fitting of which is designated 34. Hydraulic conduitry necessarily connecting the hydraulic power unit 30, 32 with cylinders powered thereby has been omitted from the drawings, as well as other necessary fluid pressure conduitry, electric limit switch wiring and the like. This is done in the interest of simplicity and clarity, and because the nature of such connections will be obvious to those of ordinary skill in the art, once the nature of the desired motions and control thereof is understood. FIG. 14 shows an actual suggested wiring layout.

The tracer head 24 includes a feeler unit 36, proper, carried at the end of a parallel arm-type support 37, which is in turn pivotally mounted at the rear thereof on the oscillatory plate structure 27, details of which will be hereinafter set forth. The vertical position of support 37 is adjusted and maintained through the agency of a pneumatic lift and lower cylinder 39, with speed control over this movement exercised by a dashpot unit 40.

In reference to the vertical support of the belt finishing contact wheel Wh about which the endless belt B! is trained, this wheel as illustrated in FIG. 4, is carried by a pivotal arm support device 42 which is itself mounted to the oscillatory, vertically adjustable, dovetail-type plate 28 mentioned above. Features of structure and operation of this mount, as articulated to swing in unison with the oscillatory dovetail mount at 27 for the tracer head 24, are hereinafter described in greater detail. For the time being, it suffices to state that the contact roller mounting arm 42 presents the motor-driven polishing belt 81 to the workpiece W under pneumatic pressure exerted on the arm by an air cylinder 43, and under the speed control of a dashpot device 44.

The reference numeral 46 (FIG. 1) generally designates a control valve unit appropriately mounted to the machine framework, at which pneumatic adjustments featuring the operation of the tracer head cylinder 39 and the belt head cylinder 43 are made; the reference numeral 47 designates another valve unit, including speed control needle valves (not shown) for the governing of operation of various hydraulic cylinder units; the reference numeral 48 designates an electrical terminal box; and the reference numeral 49 designates a pushbutton control box. Features and the operation of the various basic operating components, as heretofore broadly set out, will now be described in somewhat greater detail as to structure.

INDEXING AND TRAVERSING ASSEMBLY This mechanism, as generally designated 12 and best shown in FIGS. 5 and 6, considered tin conjunction with FIGS. 1-4, is one through which the front-to-rear reverse indexing and the horizontal side-to-side reciprocatory traversing motions of the template and workpiece holding subassemblies 18, 19 are effected. Its lowermost, front-to-rear and reversibly indexing subassembly 14 is shown, as indicated above, as comprising the elongated rectangular baseplate 11 having rigid upright front and rear end bracket members 51, to which the ends ofa pair of elongated parallel guide rods 52 are rigidly connected. These rods each extend through and guide aligned ball bushings 53 fixed to and depending beneath a bottom plate 54 of the side-to-side traversing subassembly or unit 13. Plate 54 also carries a pair of load rollers 55 at the bushings 53, these rollers riding the top of the baseplate 11, so that the unit 13 has a highly efficient antifriction sliding mount, as guided on rods 52, in the front-to-rear indexing action, and vice versa. If desired, and in order to attain more stability, the load rollers may be on more widely spaced tracks, as indicated in dot-dash line at 55' in FIG. 2.

The guide rods 52 are shielded by elongated compressible and extensible corrugated sleeves 56 fastened at their outer ends to the respective rods and at their inner ends to the housings of the ball bushings 53. The structure may be further shielded, if desired, by cover plates 57 extending inwardly from the tops of the end brackets 51. Plate 54 carries a central depending side flange extension 59, and the end of the plunger 61 ofa horizontal hydraulic cylinder 62 is operably connected to the extension 59. Cylinder 62 is itself anchored to the forwardmost of the two upright brackets 51 on baseplate 11.

Similar provisions are made to mount the plate 15, which supports the pivot units 16, 17, for the horizontal back-andforth traverse of the template and workpiece holders. That is, plate 54 has a pair of upright end brackets 63, and a hydraulic cylinder 64 paralleling and between guide rods 65 is anchored to one of these brackets, with the plunger 67 of this cylinder being operably connected to plate 15. This is done through the agency of a generally rectangular platen 68 atop which the plate is welded or otherwise fixedly secured. Platen 68 carries a depending bracket 69 at one end thereof to and under which the plunger 67 is operatively connected.

Platen 68 carries beneath it sets of ball bushings 70 to guide the same on the rods 65 and, as in the case of the other pair of guide rods 52, the guide rods 65 are shielded by encircling corrugated flexible sleeves 71, secured thereto at their outer ends and at their inner ends to the housings of ball bushings 70. The load of platen 68 and the template-workpiece support plate 15 is borne by roller 72 on the platen or bushings 70, which rollers ride the top of the baseplate 54 of the side-toside traverse unit 13.

As shown in FIG. 2, the side-to-side traverse plate 15 carries an extension rod 72 having spaced abutments 72 thereon which engage an upright stop 73 on the right-hand traverse plate bracket 63 as the template and workpiece holders 18, 19

reach their intended side-to-side traverse limits. This prevents an undesirable and wasteful overtravel. The lower front-to rear indexing subassembly 14 has similar motion stop means.

TEMPLATE-WORKPIECE HOLDER AND COUPLING ASSEMBLY This assembly, as best illustrated in FIGS. 1, 2, 7 and 8, generally comprises the upright antifriction pivot units 16, 17 mounted adjacent opposite ends of the platen-supported traversing and indexing slide 15, the linkage 23 periodically powered by the hydraulic jogger cylinder 22, and the template and workpiece holder devices 18, 19, respectively, as operated for a pivotal swing of slight angular extent about the respective axes of units 16 and 17 by the cylinder and linkage 22, 23, i.e., coordinately about a horizontal axis including the special universal joint 20.

Pivot unit 16 has internal antifrictional bearing means (not shown) supporting a transverse rocker arm 74, atop which there is fixedly mounted a rigid baseplate 75 of the template holder 18; and this baseplate is equipped with a pair of Iongitudinally spaced, horizontally adjustable tappet or cam bars 76, 77. These members enter into the control of the duration and extent of the movements of the holder units l8, 19, as traversed horizontally by the main traversing and indexing assembly 12.

The base member 75 of template holder 18 is equipped with upright head and tail stock members 78, 79, respectively, features of which will be hereinafter described in greater detail. Members 78 and 79 serve to fixedly clamp the ends of the predeterminedly, specially and very accurately shaped template T, and the reversing traverse action of holders l8 and 19 originates in the engagement of the cam members 76 and 77 with an appropriate limit switch LS-I, which appears in the schematic view of FIG. 13, as well as in FIG. 14.

The upright pivot unit 17 is constructed identically to the unit 16 and supports at its top a horizontally elongated base member 81 rigidly connected to the workpiece holder subassembly 19. This support is effected through the agency of an arm 82 keyed to and pivotally supported by unit 17 and extending eccentrically of the vertical axis of that unit. Holder base 81 rigidly supports an upright head stock 83 of the holder unit 19, as well as a tail stock 84 substantially spaced axially from the head stock, and members 83 and 84 fixedly clamp workpiece W therebetween in generally coaxial relation to the template T. The head and tail stock members 78, 79 and 83, 84 will be hereinafter referred to. As indicated earlier, the typical workpiece W is a turbine compressor blade, approximately one-half of which is duplicated in exact intended outline and extent by template T. When this half of the workpiece has been completed by the machine, a different template may be employed in finishing the other half, upon reversal of the workpiece endwise. This may entail a substitution of different head and tail stock designs, but such a factor is not germane to the invention.

For the purpose of articulating the holder units 18, 19 for very limited periodic oscillation about the upright axes of pivot units 16, 17 respective, as indicated by arcuate arrows D in FIG. 1, the forward end of the rocker arm 74 is connected to the arm 82 of unit 19 by an elongated adjustable turnbuckle-type link 86 of the connecting rod unit 23, of which arms 74, 82 and link 86 are component parts. Link 86 connects to arms 74, 82 at eye-shaped ends 86 of the link. This connecting rod unit is jogged in slight increments of horizontal angular motion, only in the event the workpiece W and template T have nonparallel longitudinal edges. The jogging action stems from the agency of the hydraulic power cylinder 22, the plunger of which (not shown) is connected at 22' (FIG. 8) to the end of rocker arm 74 opposite the end at which the connecting rod or link 86 is articulated at 86'. Cylinder 22 is horizontally mounted by an upright bracket 87 on horizontal traverse plate 15.

In the instanced case in which a nonparallel sided workpiece or blade W is being finished, cylinder 22 transmits a slight mechanical jogging impulse to rocker arm 74 at the end of each traversing workpiece cycle. These, as transmitted through linkage 23, enable the polishing or finishing head H to maintain a line of action at all times parallel in the horizontal sense to the zones of workpiece W which the latter traverses horizontally and longitudinally to-and-fro beneath the head. This signifies in particular the incremental zones at which the head makes the initial contact with one edge of and leaves the opposite edge of the nonparallel edged workpiece, not to mention intermediate overlapping and merging zones therebetween.

FIG. 7 and 8, considered in conjunction with FIGS. 1 and 2, best illustrate for the purpose of the present description structural features of the head and tail stock members 78, 79 of template mounting unit 18, the head and tail stock members 83 and 84 of workpiece holder 19, and the special universal joint which substantially coaxially connects the template T and workpiece W for conjoint limited and cam-derived rotation about a substantially common horizontal axis.

Thus, as best shown in FIGS. 7 and 8, there is an upright bracket 88 of the template head stock subassembly 78 which rotatively journals on a horizontal axis a head stock 89. This device is equipped with jaws 90 which clamp the template T at one end thereof.

Bracket 88 is shown (FIG. 8) as being mounted upon the oscillatory plate 75 carried by rocker arm 74, this plate providing elongated parallel slots 91 which enable the tappet or cam bars 76, 77 to be adjusted as to angularity, then clamped rigidly in any adjusted relationship, as suggested in FIG. 1, to determine the limit stop-controlled extent of template-workpiece traverse.

The tail stock device 79 of the template mounting subassembly 18 includes an upright bracket 93 on the end of plate 75 opposite head stock 78. Bracket 93 journals a rotatable tail stock 94 having jaw means at 95 to clamp the right hand (FIGS. 2, 7, and 8) of template T. The template tail stock 94 includes a knuckle or clevis member 96 projecting through the bracket 93, at which clevis the template mounting unit 18 is operatively connected to the universal coupling 20.

The head stock device 83 of workpiece holding unit 19 is, as shown in FIGS. 7 and 8, operatively coupled to the universal joint 20 (later to be detailed) at a left-hand clevis or knuckle member 100 of the device. Head stock 83 further comprises an upright bracket 101 having an elongated horizontal base extension 102 (FIG. 1) which is bolted to the base 81 of the workpiece holding unit 19. The coupling clevis 100 is horizon tally journaled in a top boss 103 of bracket 101, and to the right of the latter it carries a two-part clamp 104, in which the left-hand end of the workpiece blade W is clamped. The clamp 104 is loosened and tightened upon manual operation of an associated handpiece 105.

The right-hand end of workpiece holding base 81 (FIGS. 1 and 8) has an upright bracket 107 bolted atop the same; and this bracket carries tubular top bosses 108 and 109, in aligned bores of which the centering point 110 of the tail stock device 83 is coaxially received, being in known manner in threaded internal engagement with boss 108. Similarly in known manner, the tail stock member 110 is operated axially through the agency ofa hand wheel 111, centering in a usual way in a recess in the right-hand end of workpiece W. As has been noted before, when the workpiece is reversed to polish this right-hand end thereof different types of workpiece head and tail stocks may be required. See, however, the later comment in this matter.

Reference being had to FIGS. 7 and 8, again in conjunction with FIGS. 1 and 2, the special universal coupling 20 is of a two-part, axially slidable type. It includes an elongated sleeve 113 having a cylindrical bore 114 therethrough which is broached to afford a spline groove 115; and sleeve 113 is pinned to a right-hand clevis 116 which mates with the clevis 100 of workpiece head stock 84.

The other main component of universal joint 20 is an elongated rod 117 axially at one end received in sleeve bore 114 and having a splined, axially slidable rotary drive connection to the spline groove ofsleeve 113. Rod 117 is pinned at its opposite end to a clevis 118 mating with the clevis 96 of template tail stock 94. An axially expansible and compressible shield 117' of helically coiled spring steel stripping surrounds rod 117 between sleeve 113 and clevis 118, shielding the rod.

Accordingly, when the template T is slowly oscillated under the reactive camming force thereon of ball unit 21 as the template traverses horizontally beneath tracer head 24, the rotary action is transmitted faithfully through coupling 20. The sleeve and rod components 113, 117 of the latter will have relative axial slide as this takes place; and all of the compounded motions of the workpiece and template are accommodated, coincidental with the rotative transmission of torque through coupling 20.

TRACER SUBASSEMBLY AND ROCKING MOUNT THEREOF The subassembly of tracer head 24, and its connection to 'the dovetail-type plate structure 27 mounting the same to the upright wall 26 of the apparatus, are best illustrated in FIGS. 9I2, inclusive, reference being also had to FIGS. 1 and 3. Head 24 comprises a vertically elongated and relatively massive body block 119 (FIGS. 11 and 12) of rectangular cross section which is connected by bolts 121 between parallel arm plates of the pivoted support arm structure 37', and further details of this structure and its mount to the oscillatory plate device 27 will be hereinafter described.

Block 119 has a pair of vertically elongated parallel bores 122 extending therethrough, which are counterbored at their upper and lower extremities to receive fixed bushings 123. These floatingly guide a pair of elongated tappet rods 125; and the bottoms of these rods lie directly over a rocker 127 of inverted U-shaped cross section. The rocker is pivotally mounted by a transverse pin 128 between a pair of arcuate bottom ears 129 integral with tracer body block 119; and a pair of template feeler rollers 130 are rotatively journaled by pins 131 between the arms of rocker 127. As shown in FIG. 11, the feeler rollers are ofquasi-spherical shape, so as to have not only rolling and feeling contact with the top surface of template T as the latter travels horizontally beneath head 24, but also to present a minimum frictional engagement with the template as the latter is rocked about a horizontal axis under the influence of reaction unit 21, coincidentally with the horizontal traverse.

As best illustrated in FIG. 11, reference being also had to FIGS. 1 and 3, the ball reaction unit 21 is rigidly mounted upon a horizontal and rearward-to-front extending bracket strap 132, which is in turn welded or otherwise rigidly secured (FIGS. 1, 2, and 3) to an angle iron bracing structure 134 rigidly connected to the machine base 10 and the upright wall 26 of the apparatus. (FIG. A hardened antifriction reaction ball 135 of unit 21 (FIG. is supported by a block 136 located, as indicated in FIG. 12, directly beneath the tracer heads feeling roller rocker 127, being centered horizontally between the rollers 130 carried by the latter. A highly efficient antifriction journaling or reaction ball 135 for universal rolling action in block 136 is afforded by a number of hardened bearing balls 137, which are interposed in a semispherical, upward facing seat 138 in block 136 between the latter and ball 135. The block 136 is adjustably mounted to the end of bracket strap 132 through the agency of a central depending stem 139 threaded into the arm and provided with a coacting lock nut 140.

The tracer head block 119 fixedly mounts at its top, as best shown in FIGS. 11 and 12, a limit switch unit, generally designated 142, comprising a pair of transversely spaced limit switches LS-S and LS-6 each having a depending operating plunger 143. The lower ends of these directly overlie horizontal tappet extensions 144 on the tops of the two floating rods 125. Switches LS-S and LS-6 are of the normally open type, and there is a very small clearance of, say 0.003 inch, between the same and the extensions 144 when the tracer head feeler rollers are in a neutral position, normally with their axes in a horizontal plane.

Accordingly, upon a deflection of one or the other of the rollers 130 in excess of this clearance dimension, as the template T traverses horizontally beneath tracer head 24 in the direction of the double headed arrow in FIG. 12, the corresponding tappet rod 125 causes the associated limit switch LS-S or LS-6 to close for such time as the deflection remains in effect. Resultantly energized circuitry (not shown) wired to the switch in turn operates appropriate solenoid valve means (also not shown), with the result that the hydraulic cylinder unit 25 behind the machine wall 26 (FIG. 4A) is pressurized in one direction or the other. This, through the agencies of other linkage provisions to be described, causes parts of the respec tive oscillatory mounting plate units 27, 28 to be swung appropriately but limitedly for the purpose of adjusting finishing belt Bl, as trained about contact wheel Wh, to maintain a fixed, line-contact finishing engagement with the horizontally traversing and axially rocking surface of workpiece W.

Coincidental with this action as effected through mounting plate structure 28, the tracer head mounting plate structure 27 is correspondingly swung in a manner to shift head 24 to a position angularly corresponding with that of contact wheel Wh. Thus normalized or neutralized again, one or the other of its tappet rods 125 drops away from the associated limit switch plunger 143, reopening that switch and depressurizing the oscillating cylinder 25.

This situation obtains until another deflection of the feeler rollers in one sense or the other arises to reclose a switch LS-S or LS-6, energize the associated electric circuitry and repressurize hydraulic cylinder unit 25 in direction or another for a further oscillatory adjustment of plate devices 27 and 28, along with the respective tracer head and finishing heads respectively carried thereby.

As shown best in FIG. 11, the body block 119 of tracer head 24 is secured by bolts 146 to a backing plate 147 spanning the arm parts 120 of spacer head mounting structure 37. These arm plates are hingedly connected by antifriction bearing or bushing means 148 to a pair of further parallel arm members 149 of structure 37, which arms 149 are of substantial length, as appears in FIGS. 3 and 9, and are journaled at their rear end to bracket means 150 carried by the oscillatory mounting plate structure 27, in a manner hereinafter described.

The connection of arms 149 to bracket 150 is through the agency of antifriction bearing or bushing means at 151', and a turn buckle-type connecting link 152 is pivotally connected at its opposite ends to one of the hinged arms 120 of structure 37 and to a depending crank 153 fixed to one of the arms 149 at the bushing 151. This completes the parallelogram-type linkage structure 37 adjustably sustaining the tracer head 24.

The pneumatic lift cylinder 39 and dashpot type speed control unit are operatively connected downwardly to structure 37, as at one of the arm components 149 of the latter, so that upon pressurization of cylinder 39 in one direction or another, the head 24 is lifted or lowered with insignificant frictional resistance, speed of movement being regulated by unit 40. Units 39, 40 mount on an arm 154 atop bracket 150.

OSCILLATORY HEAD ADJUSTMENT STRUCTURE- TRACER HEAD As best illustrated in FIGS. 9 and 10, but also shown in FIGS. 1, 3, and 4, the oscillatory mounting structure 27 comprises a relatively massive mounting plate 155 which is of generally rectangular outline, and is pivotally mounted adjacent to its bottom to the machine wall 26 by a heavy duty pin 156. As indicated in FIGS. 2, 9, and 10, this pin and the pivotal axis of tracer roller rocker 127 are substantially in front-torear alignment. As also appears best in FIG. 10, the top edge 157 of oscillatory plate 155 is mildly arcuate convexly, and in this top zone the plate has front-to-rear restraint exerted thereon by an arcuate retainer 158 fixed to wall 26 which is of inverted L-shaped cross section, presenting an integral lip 159 overlapping the top and front of plate 155. The pivotal adjusting action of plate about its axis at pin 156 is shown in a somewhat exaggerated way in dotted line in FIG. 10, this action stemming from pressurization of hydraulic cylinder unit 25 and being transmitted mechanically through associate provisions to be described.

A second component of the oscillatory plate mount 27 is a dovetail-recessed vertical way member 160 fixedly secured to the forward face of plate 155, this way matingly receiving a dovetail-type guide block 161. The block has an upright screw-threaded adjusting screw 162 in threaded engagement therewith but restrained from axial motion relative to dovetail way 160, in a conventional manner, whereby a rotary adjustment of screw 162 occasions a vertical adjustment one way or another of guide block 161. The bracket means 150 sustaining the tracer head arm structure 37 is bolted to the forward face of the guide block 161.

Referring now to FIG. 4A, from which the features of arm structure 37 and bracket means 150 have been omitted, the oscillatory plate 155 is equipped with a rear boss 164 which projects through an elongated arcuate slot 165 in the machine wall 26; boss 164, as shown in FIG, 9, is located adjacent the top of plate 155, well spaced above the latters pivot pin 156. An eye-shaped end 166 of the plunger 167 of hydraulic cylinder unit 25 is operatively connected to a pin projecting from boss 164.

OSCILLATORY HEAD ADJUSTMENT-FINISHING HEAD The cylinder body 168 (FIG. 4A) of the hydraulic unit 25 is anchored on a bracket 169 rigidly secured to and projecting from the rear of machine wall 26; and a vertically offset extension 170 of cylinder plunger 167, as connected in common with the latter onto a piston (not shown) of unit 25, is operatively connected at its eye-end 171 to the oscillatory finishing head plate mount 28 in a manner presently to be described. As appears in FIGS. 3, 4, 4A and 4B, the machine wall 26 is rearwardly buttressed by a number of upright bracing plates 172 of triangular shape.

The mounting plate structure 28 for the finishing head, generally designated H, is comprised of contact wheel Wh and belt Bt, as described before, and is to a considerable degree substantially identical to the oscillatory mounting plate structure 27 for tracer head 24. Accordingly, to the extent of such similarities, corresponding parts will be designated by corresponding reference numerals, primed, and further description thereofin detail will be dispensed with.

As indicated in FIGS. 2 and 4, the pivot pin 156' by which oscillatory adjustment plate 155' is mounted adjacent the latters bottom, is in substantial transverse alignment with the point at which workpiece W is clamped by the head stock device 78 of the workpiece holder subassembly 19, just as the pivot pin 156 for oscillatory tracer head mounting plate 27 substantially aligns transversely with the pivot at pin 128 of rocker 127 of head 24. Accordingly, the pivotal adjustment of plates 155, 155' about these axes (I156, 156' respectively) under motivation by hydraulic cylinder subassembly 25 are identical.

As appears in FIGS. 2 and 4, the mounting arm structure 42 by which contact wheel Wh for belt B! is sustained, has a rearward pivotal mount on a horizontal axis at 173 to a large bracket 174 fixed to the forward face of the vertical, adjustable, dovetailed block 161' which is guided in the dovetail way 160 of oscillatory adjusting unit 28, so that finishing head H and its mounting arm structure 42 will adjust angularly identically to the tracer head 24 and its mounting structure at 27.

Bracket 174 has a protective housing 175 (FIGS. 1 and 2) encasing and journaling one side thereof, the housing having a pivotal mount on bracket 174 about the axis 173. This is the axis of the motor shaft. Motor 176 has a drive connection to wheel Wh through a power transmission chain or belt 177. The finishing head's pneumatic lift cylinder 43 and speed control dashpot unit 44, as carried on a bracket 178 projecting forwardly of wall 26, are operatively connected downwardly to a member 179, fixed externally on housing 175, in a manner generally corresponding with the connection of the cylinder and dashpot 39 and 40 of tracer head support structure 37 are connected unit 27.

For the rest, the base 81 of workpiece holder unit 19 is equipped with an appropriate coolant shield, generally designated S, to receive and carry away coolant directed to workpiece W by circulating means (not shown). Such means includes timed means to dispose of the swarf collected in the coolant. The belt and wheel head H is shielded by an elongated sheet metal casing C, and belt BI is trained upwardly in this casing about a suitable idler pulley (not shown).

The control panel 49 (FIGS. 1 and 2) presents a number of manual pushbuttons connected, for example, to effect a manual jogging of the template and of workpiece holders 18 and 19 about their vertical respective axes, to override any normally automatic motion, etc.

The machine is governed by electrical, hydraulic and pneumatic circuitry, including limit switches, timing relays, counters, solenoid operated valves and the like, as indicated above, but as also indicated, it is deemed undesirable to unduly com plicate the disclosure in reference to specific features of such systems, except as generally indicated in FIG. 14. A reference to FIG. 13 will sufiice to explain the timed operation of the numerous component units and subassemblies referenced above.

OPERATION As schematically indicated in FIG. 13, the template-andworkpiece carrying, front-to-rear indexing slide 54 has fixedly connected operatively thereto a relatively elongated tappet member 182 and a shorter tappet member 183, closely adjacent to its forward end. With the template T and workpiece W properly clamped on holder subassemblies 18, 19, the operator manually positions the slidable traversing and indexing slide members 15, 54, respectively, appropriately adjusts the various cam and limit switches of the machine, then sets the equipment in automatic operation by depressing a master pushbutton at panel 49.

At this time, the belt head H is elevated by cylinder 44, the tracer head 24 is elevated by cylinder 39, the transverse indexing plate 54 is in its extreme forward or frontwise position, and the traversing slide plate is in its extreme left-hand position. The limit switch LS-l (FIG. 13) is set to be tripped by cam bar 77 when an initial traverse stroke to the right has been completed by plate 15.

However, this does not take place until the indexing slide plate 54, as powered by the hydraulic cylinder 62, carries the tappet member 182 sufficiently transversely to trip limit switch LS-2. The template and workpiece W are at this time directly beneath the tracer head 24 and the finishing belt Bt of the head H, respectively. Switch LS-2 is electrically connected in the wiring circuitry, as shown in FIG. 14, to operate a solenoid valve means controlling the admission of compressed air to the respective pneumatic cylinders 39 and 43, which thereupon drop the tracer and finishing heads under timed control by the respective dashpot devices 40 and 44. The rightward traverse of template and workpiece carrying plate 15 then proceeds until switch LS-I is tripped by cam bar 76 on the slide plate 15.

When this happens the indexing slide plate 54 is powered by hydraulic cylinder 65, under the control of repeatedly operated timing relay means, to momentarily travel a slight increment of movement to the rear, in preparation for a second traversing stroke beneath finishing belt BI. The indexing action referred to is under the control ofa solenoid valve device, as governed by the repeater relay means referred to. However, if it is desired such timing relay means may be set to enable a complete two-way reciprocation, or more than one reciprocation, of the slide 15 before the cylinder 64 and slide 54 index it to the rear.

The left-hand stroke of slide 15 terminates when limit switch LS-I is tripped by cam bar 77; there is another incremental index shift of slides 15 and 14 to the rear, and the coordinated traversing and indexing motions described above are repeated until the full surface of the workpiece W has been finished, whereupon tappet member 182 on indexing plate 54 trips the in" feed reverse limit switch LS-3, to terminate the indexing operations to the rear.

As these actions are taking place, tracer head 24 senses the surface of template T in the right-left reciprocating slide traverses, its feeler rollers 130 and associated tappet rods causing limit switch LS-S and LS-6 (FIG. 14) to be closed and opened in the manner described above, thereby maintaining a proper angle of feeling engagement of tracer head 24 with the template and a proper flush line engagement of finishing belt Bt with the workpiece surface.

Likewise as the indexing and traversing motion takes place, and in the event the blade W or like workpiece object is nonparallel sided, appropriate timing means in the electrical circuitry of FIG. 14 controls appropriate valving means to cause slight jogging pressurizations of hydraulic cylinder unit 22. From these, as transmitted through linkage 23, the lines of action of tracer head 24 and belt B! are caused to parallel the leading and trailing edges of template T and workpiece W as finishing commences and ends, the incidental effect being to cause some degree of mergence of the longitudinal finishing zones along the workpiece in intermediate phases.

The tripping of limit switch LS-3 by tappet 182 referred to above occasions a reverse pressurization of the indexing slides hydraulic cylinder 62, and plate 54 returns fully outwardly or forwardly, where its tappet member 183 trips the out" feed reverse limit switch LS-4. The plate slides 15, 54 and template and workpiece holders 18, 19 carried by the former are now in their original starting positions. Operations of switch LS-4 causes interlocked circuitry in FIGS. 14A and 148 to become in a condition to recommence the traverse and index cycles in the manner described above.

The limit switch LS7 appearing in FIG. 13 is wired in the electrical circuitry so that, upon being tripped at the completion ofjogging operations originating at cylinder 22, the latter is reversely pressured to return the oscillatory plate devices 27 and 28, respectively, which support the tracer and finishing heads 24 and H to their original angular position in relation to the respective pivots 156 and 156'.

Limit switch LS-8 is a safety device included in the electri' cal circuitry to insure that a finishing operation will start only when the tracer head 24 is up. Limit switch LS-9 is also a safety device to cut out the entire machine operation in the event of a breakage offinishing belt 8!. Switch LS-9 does not appear in FIG. 14. However, it is wired directly in circuit with the secondary winding of a power transformer energizing the machine; and other control means are also wired across leads supplied by the transformer secondary.

It is to be observed, with reference to FIGS. 1 and 2, that the blade workpiece W carries a stiffening midspan member M. In the operation of the machine as above-described, the finishing head H acts only in traverse and indexing stroke on the surface area of the blade between the head stock 83 and midspan M, the workpiece being then removed and finished as to other surfaces thereof by further means; and this necessarily entails four different finishing cycles. However, it is possible to reduce the total number of cycles to but two, in which an entirely upwardly facing workpiece surface can be finished between head stock 83 and tail stock 84, whereupon the workpiece is removed and separately finished as to its other or opposite surface.

This is made possible by in effect approximately doubling the total traverse operation of the workpiece W, as represented by two equal one-half traverses, employing a template T of correspondingly increased length, and by elevating the finishing head structure H, along with that of tracer head 24, when one portion of the workpiece surface has been finished. This is then followed by a repetition of its finishing operation on the workpiece surface on the opposite side of midspanner M. This increase in the output capacity of the machine is made possible by a simple alteration in the scheme of programming the cycling thereof, not requiring any mechanical change in the operating parts. That is, the control circuitry of FIG. 14 is altered by incorporating therein certain control and timing relay means and other related provisions, but still without alteration of the basic nature of the circuit. The apparatus remains essentially the same in regard to the various compounded motions of its subassemblies, and the means for producing these motions.

What I claim is:

l. A compound-action workpiece finishing machine to act on a workpiece having a surface which has portions in angular relation to one another in respect to both the horizontal and the vertical directions; comprising a traversing workpiece holder having means to rigidly clamp a workpiece, a template presenting a surface corresponding with that of the workpiece, a traversing template holder having means to rigidly clamp said template, means coupling said holders to one another for a joint simultaneous motion thereof about substantially coaxial horizontal and/or horizontally spaced vertical axes, respec tively, during at least a part of a traverse movement thereof, means to impart said traverse movement, and means to index said holders transversely of the direction of the traverse movement in timed relation to the latter.

2. A compound-action workpiece finishing machine to act on a workpiece of elongated nature which has a surface between its longitudinal edges presenting portions in angular relation to one another in respect to both the horizontal and vertical directions; said machine comprising a traversing workpiece holder having means to rigidly clamp the workpiece at opposite longitudinal ends thereof, a template of elongated nature presenting a longitudinal portion between longitudinal side edges thereof which corresponds in cross section with that of the workpiece, a traversing template holder having means to rigidly clamp said template at opposite ends thereof, means to longitudinally traverse said holders as a unit, including means drivingly coupling said workpiece and template holders in end -to-end relation to one another for said traverse means actuating said holders for a swing thereof about a substantially common axis generally paralleling the length thereof during said traverse, and means to index said holders transversely of the direction of the traverse movement in timed relation to the latter.

3. The finishing machine of claim 2, in which said coupling means comprises a universal joint drivingly connecting said holders in end-to-end relation to one another.

4. The finishing machine of claim 2, and further comprising tracer and finishing heads engageable respectively with the template and workpiece in the traverse thereof, and means operatively connecting the finishing head to the tracer head to maintain the finishing head in predetermined angular relation to the workpiece surface during the traverse movement.

5. The finishing machine of claim 3, and further comprising tracer and finishing heads engageable respectively with the template and workpiece in the traverse thereof, and means operatively connecting the finishing head to the tracer head to maintain the finishing head in predetermined angular relation to the workpiece surface during the traverse movement.

6. The machine of claim 3, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, to swing about said substantially common axis.

7. The machine of claim 4, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, toswing about said substantially common axis.

8. The machine of claim 5, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, to swing about said substantially common axis.

9. The finishing machine of claim 1, in which said indexing means operates in timed relation to the traverse movement to shift said holders as a unit in a direction at to the direction of the traverse movement.

10. The finishing machine of claim 8, in which said indexing means operates in timed relation to the traverse movement to shift said holders as a unit in a direction at 90 to the direction of the traverse movement.

11. The finishing machine of claim 1, in which said traverse movement imparting means comprises a support on which the template and workpiece holders are mounted, and means to move said support in one direction, said indexing means comprising a further support, and means to move said further support at 90 to the movement of the first named support, and means to mount one of said supports for its movement on the other support.

12. The finishing machine of claim 8, in which said traverse movement imparting means comprises a support on which the template and workpiece holders are mounted, and means to move said support in one direction, said indexing means comprising a further support, and means to move said further support at 90 to the movement of the first named support, and means to mount one of said traverse movement imparting and indexing supports for its movement on the other of said support.

13. The finishing machine of claim 4, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.

14. The finishing machine of claim 5, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.

15. The finishing machine of claim 6, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.

16. The finishing machine of claim 8, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.

17. The finishing machine of claim 13, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.

18. The finishing machine of claim 14, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.

19. The finishing machine of claim 15, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.

20. The finishing machine of claim 16, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.

21. The finishing machine of claim 17, in which the tracer head has electrical limit switch means controlling the operation of said linkage.

22. The finishing machine of claim 20, in which the tracer head has electrical limit switch means controlling the operation of said linkage.

23. A finishing machine in accordance with claim 2 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.

24. A finishing machine in accordance with claim 3 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.

25. A finishing machine in accordance with claim 4 which as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.

26. A finishing machine in accordance with claim 8 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head. 

1. A compound-action workpiece finishing machine to act on a workpiece having a surface which has portions in angular relation to one another in respect to both the horizontal and the vertical directions; comprising a traversing workpiece holder having means to rigidly clamp a workpiece, a template presenting a surface corresponding with that of the workpiece, a traversing template holder having means to rigidly clamp said template, means coupling said holders to one another for a joint simultaneous motion thereof about substantially coaxial horizontal and/or horizontally spaced vertical axes, respectively, during at least a part of a traverse movement thereof, means to impart said traverse movement, and means to index said holders transversely of the direction of the traverse movement in timed relation to the latter.
 2. A compound-action workpiece finishing machine to act on a workpiece of elongated nature which has a surface between its longitudinal edges presenting portions in angular relation to one another in respect to both the horizontal and vertical directions; said machine comprising a traversing workpiece holder having means to rigidly clamp the workpiece at opposite longitudinal ends thereof, a template of elongated nature presenting a longitudinal portion between longitudinal side edges thereof which corresponds in cross section with that of the workpiece, a traversing template holder having means to rigidly clamp said template at opposite ends thereof, means to longitudinally traverse said holders as a unit, including means drivingly coupling said workpiece and template holders in end-to-end relation to one another for said traverse means actuating said holders for a swing thereof about a substantially common axis generally paralleling the length thereof during said traverse, and means to index said holders transversely of the direction of the traverse movement in timed relation to the latter.
 3. The finishing machine of claim 2, in which said coupling means comprises a universal joint drivingly connecting said holders in end-to-end relation to one another.
 4. The finishing machine of claim 2, and further comprising tracer and finishing heads engageable respectively with the template and workpiece in the traverse thereof, and means operatively connecting the finishing head to the tracer head to maintain the finishing head in predetermined angular relation to the workpiece surface during the traverse movement.
 5. The finishing machine of claim 3, and further comprising tracer and finishing heads engageable respectively with the template and workpiece in the traverse thereof, and means operatively connecting the finishing head to the tracer head to maintain the finishing head in predetermined angular relation to the workpiece surface during the traverse movement.
 6. The machine of claim 3, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, to swing about said substantially common axis.
 7. The machine of claim 4, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, to swing about said substantially common axis.
 8. The machine of claim 5, in which a reaction device camming engageable during said traverse movement with a template surface causes said template and workpiece holders, as drivingly connected by said coupling means, to swing about said substantially common axis.
 9. The finishing machine of claim 1, in which said indexing means operates in timed relation To the traverse movement to shift said holders as a unit in a direction at 90* to the direction of the traverse movement.
 10. The finishing machine of claim 8, in which said indexing means operates in timed relation to the traverse movement to shift said holders as a unit in a direction at 90* to the direction of the traverse movement.
 11. The finishing machine of claim 1, in which said traverse movement imparting means comprises a support on which the template and workpiece holders are mounted, and means to move said support in one direction, said indexing means comprising a further support, and means to move said further support at 90* to the movement of the first named support, and means to mount one of said supports for its movement on the other support.
 12. The finishing machine of claim 8, in which said traverse movement imparting means comprises a support on which the template and workpiece holders are mounted, and means to move said support in one direction, said indexing means comprising a further support, and means to move said further support at 90* to the movement of the first named support, and means to mount one of said traverse movement imparting and indexing supports for its movement on the other of said support.
 13. The finishing machine of claim 4, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.
 14. The finishing machine of claim 5, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.
 15. The finishing machine of claim 6, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.
 16. The finishing machine of claim 8, in which said tracer and finishing heads are mounted to move pivotally on parallel axes transverse of the direction of the traverse movement for the purpose of maintaining a corresponding angular relation to the template and workpiece surface.
 17. The finishing machine of claim 13, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.
 18. The finishing machine of claim 14, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.
 19. The finishing machine of claim 15, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.
 20. The finishing machine of claim 16, in which said heads are operatively connected by a fluid pressure-powered linkage for said pivotal movement, said tracer head controlling the operation of the linkage.
 21. The finishing machine of claim 17, in which the tracer head has electrical limit switch means controlling the operation of said linkage.
 22. The finishing machine of claim 20, in which the tracer head has electrical limit switch means controlling the operation of said linkage.
 23. A finishing machine in accordance with claim 2 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.
 24. A finishing machine in accordance with claim 3 which, as operating on a workpiece having a nonrectiLinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.
 25. A finishing machine in accordance with claim 4 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head.
 26. A finishing machine in accordance with claim 8 which, as operating on a workpiece having a nonrectilinear longitudinal edge, has means to periodically shift the template and workpiece holder rotatively about an axis normal to the workpiece traverse to maintain a parallel relationship of the longitudinal workpiece edge to an operating member of the finishing head. 